Look fine, just remember spray the dome daily, not the cubes. Keep humidity 100%.
Also bigger cubes like that may take an extra week to show just because theres a little more cube mass to get through. Id remove the cube wrapping so you can see the entire cube and tell when they root, also youll have to cut the 4x4s to size to fit those in the bigger cubes.
Ya, just remeber though a plant isnt gunna grow roots searching for water if the cubes are soaked. Also anything that looks rotted plant matter wise, remove it so you dont get mold.
Yes just keep the cubes damp. Dont spray them everyday and dont leave standing water in the tray. And when you do spray just give the bottom of the cubes one or 2 squirts of a light mist...